ARM: at91: cpuidle: Convert to platform driver

Using the platform driver model is a good way to separate the cpuidle specific
code from the low level pm code. It allows to remove the dependency between
these two components.

The platform_device is located in the pm code and a 'set' function has been
added to set the standby function from the AT91_SOC_START initialization
function. Each SoC with a cpuidle driver will set the standby function in the
platform_data field at init time. Then pm code will register the cpuidle
platform device.

The cpuidle driver will register the platform_driver and use the device's
platform_data as a standby callback in the idle path.

The at91_pm_enter function contains a { if then else } based on cpu_is_xx
similar to what was in cpuidle. This is considered dangerous when adding a new
SoC. Like the cpuidle driver, a standby ops is defined and assigned when the
SoC init function specifies what is its standby function and reused in the
at91_pm_enter's 'case' block.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>

1 files changed, 4 insertions, 0 deletions

diff --git a/arch/arm/mach-at91/pm.h b/arch/arm/mach-at91/pm.h
index 2f5908f0b8c5..76dd1a749ebd 100644
--- a/arch/arm/mach-at91/pm.h
+++ b/arch/arm/mach-at91/pm.h
@@ -11,9 +11,13 @@
 #ifndef __ARCH_ARM_MACH_AT91_PM
 #define __ARCH_ARM_MACH_AT91_PM
 
+#include <asm/proc-fns.h>
+
 #include <mach/at91_ramc.h>
 #include <mach/at91rm9200_sdramc.h>
 
+extern void at91_pm_set_standby(void (*at91_standby)(void));
+
 /*
  * The AT91RM9200 goes into self-refresh mode with this command, and will
  * terminate self-refresh automatically on the next SDRAM access.